1. Field of the Invention
The present invention relates to novel aromatic polyethers, fluorescent resin compositions containing the same, and processes for preparing the same.
More particularly, the present invention relates to the aromatic polyethers which are particularly high in glass transition temperatures, possess excellent mechanical properties, thermal resistance, and solvent resistance, as well as generate fluorescence. Accordingly, the aromatic polyethers according to the present invention are suitable for use with materials for parts and display materials in the electric, electronic, mechanical, and automobile fields.
Furthermore, the fluorescent resin compositions containing the novel aromatic polymers according to the present invention cause no bleeding of a fluorescent ingredient and possess a favorable physical strength and thermal resistance as well as generate strong fluorescence. The resin compositions are practically advantageous for use as display materials and printing ink for advertisement, decoration and the like.
2. Description of Related Art
Recently, engineering resins with a variety of chemical structures have been developed and they are employed in the wide field ranging, for example, from automobile, electric and electronic, and precision machinery fields to office automation instrument and optical communication instrument fields. Although many aromatic polyether resins of the engineering plastics have favorable properties in some areas, they are still insufficient in many areas. And strong demands have been made to develop new materials with a variety of highly improved properties which satisfy performance demanded by users.
As such aromatic polyether resins are known a variety of aromatic polyether ether ketones, aromatic polyether sulfones, and aromatic polycyanoaryl ethers. For instance, there are known aromatic polyether ether ketones having a recurring unit as represented by the following formula: ##STR1## as disclosed in Japanese Patent Kokai No. 97,094/1978, and having a recurring unit as represented by the formula: ##STR2## as disclosed in Japanese Patent Kokai No. 90,296/1979; aromatic polyether sulfones having a recurring unit as represented by the following formula: ##STR3## as disclosed in J. Polym. Sci. A-1, 5 (1967), p. 1373; and aromatic polycyanoaryl ethers having a recurring unit as represented by the following formula: ##STR4## or having a recurring unit as represented by the following formula: ##STR5## as disclosed in Japanese Patent Kokai Nos. 14,270/1972, 206,433/1984, 162,523/1986, and 223,226/1987. These aromatic polyether resins have a thermal resistance better than conventional general-purpose plastics, however, they are not sufficiently high in glass transition temperature so that they suffer from the disadvantage that they do not have a satisfactory degree of stiffness at a temperature which is higher than their glass transition temperature.
Fluorescent resin compositions are used widely as display materials, for instance, for night markers and signs as well as decorative materials. Fluorescent resin compositions as have been conventionally used are usually prepared by blending a resin with a low molecular organic fluorescent substance. In conventional technology of preparing the fluorescent resin compositions, the resin in a bulky form is crushed and pulverized during the step of preparing the resin or after it was treated with a low molecular organic fluorescent dye such as a fluorescein, Rhodamine B or the like before it is blended. The conventional fluorescent resin compositions, however, present the difficulty of preparation, requiring consumption of a large quantity of power energy, and involve the disadvantages that they cause the bleeding of the fluorescent ingredient from the resin, reducing a mechanical strength and a thermal resistance of the resin.
In order to overcome the drawbacks of the conventional fluorescent resin compositions, fluorescent polymers have been proposed which are prepared by incorporating an organic fluorescent substance such as a fluorescein, Rhodamine B, eosine Y or the like into a thermoplastic resin such as polyethylene, polypropylene, polystyrene, polyvinyl chloride or the like. One example of such fluorescent polymers is such that an esterified phenolic hydroxy group of a fluorescein is introduced into a side chain of a polyvinyl chloride resin. These conventional fluorescent polymers, however, suffer from the disadvantages that the organic fluorescent polymeric ingredient incorporated is likely to be removable from the resin and that their thermal resistance is insufficient.
In order to overcome and improve the disadvantages from which the conventional fluorescent polymers have suffered, Japanese Patent Kokai No. 62,589/1974 proposes a fluorescent polymer obtainable by incorporating a fluorescein residue into a side chain of a polymer having a polyvinyl chain as a main chain through an amide linkage. Such a fluorescent polymer, however, is obtainable through a complex series of steps and is still insufficient in a thermal resistance.
In order to overcome and improve the difficulties and disadvantages involved with the conventional fluorescent resin compositions, Japanese Patent Kokai No. 186,767/1988 discloses a fluorescent resin composition containing a europeum complex having a benzoyl trifluoroacetone moiety as a ligand. Although this resin composition is superior in durability, its fluorescence is limited to a red color so that its use is also limited to a comparatively narrow field.